It is common practice in the bottling industry to reuse, recycle, re-wash and refill returned bottles after consumer use of the item in an effort towards economy in the industry. Synthetic glues or adhesives are commonly used to affix labels and other items to surfaces, including bottles. Exemplary disclosures of synthetic glues and adhesives are provided in U.S. Pat. No. 6,803,085, which is incorporated herein by reference in its entirety. It is desirable to fully remove soils to clean the bottles as well as remove the labeling and any remaining adhesive residue left on the surface prior to cleaning, disinfecting and reuse. Unfortunately, various adhesives, including synthetic glues can be difficult to remove from surfaces such as glass bottles and any incomplete removal presents difficulty in reusing the item. In addition, conventional removal methods may only partially remove labels and/or destroy the labels creating additional buildup in the cleaning solutions (e.g. partially degraded labels).
It is known that bottle wash additives and alkaline detergent compositions along with bottle washing operations may be used to clean returned bottles. Numerous conventional aqueous-based bottle washing compositions contains caustics, alcohols, nonionic surfactants and/or other additives. Exemplary disclosures of bottle washing operations include U.S. Pat. No. 2,976,248 titled “Bottle Washing Composition and Method,” filed Aug. 1, 1957, and U.S. Pat. No. 6,530,386 titled “Method of Cleaning Returnable Bottles,” filed Jan. 25, 2000. However, such additives and detergents often incompletely remove adhesives and leave residues or deposits on the surfaces, providing commercially undesirable results. In addition, commercially-available bottle wash additives often require repeated use to fully remove residues, utilize harsh cleaning conditions and/or require of large amounts of cleaning solutions or concentrates, all of which increase the time and cost of bottle washing.
These limitations in the practices of the bottling industry are further complicated with the removal of foil (or aluminum-type) labels, which even the harshest caustic-based label removing compositions provide little ineffective label removal. Such metallic labels are often shaped or adhered to the bottle neck presenting additional difficulties in removal of the adhesives, including additional manual labor required in the event a label removing composition in a bottle washing application is unable to completely remove the labels and/or adhesives.
It is therefore desirable to provide cleaning solutions and methods of use according to the invention that provide for the complete removal of metallic bottle labels, glues and adhesives. This is a difficult task to design cleansing compositions and methods for the removal of such adhesive and other substances.
Accordingly, it is an objective of the claimed invention to develop methods for complete removal of various types of adhesives and other residues from surfaces, such as metallic labels and adhesive residue on returnable glass bottles.
A further object of the invention is novel label removing compositions for removal of various labels, including the most difficult to remove aluminum labels from glass bottles.
A still further object of the invention is to develop methods for removal of adhesive labels and residue at reduced temperature, including ambient or room temperature.
A still further object of the invention is to develop methods for removal of adhesive labels and residue at reduced caustic levels, i.e., in an amount from about 0 wt-% to about 2 wt-%, including use of label removing compositions which are caustic-free.
A still further object of the invention is to develop methods for removal of adhesive labels and residue in a period of less than about 30 minutes, and preferably less than about 15 minutes.
A still further object of the invention is to develop methods for removal of adhesive labels without destroying the labels and/or causing pulping. These and other objects of the invention are illustrated in the description of the invention. Other objects, advantages and features of the present invention will become apparent from the following specification taken in conjunction with the accompanying drawings.